feat(newlib): add option to disable eval of expression in assert() when NDEBUG set

According to the standard assert(X) should be replaced by a void expression when
NDEBUG is set. IDF's behavior was to not trigger an assertion, but we would still
evaluate X, e.g. if X was a function it would be ran.

This MR adds a kconfig option CONFIG_COMPILER_ASSERT_NDEBUG_EVALUATE which allows us
revert the behavior to be inline with the standard.

With IDF v6.0 the plan is to make CONFIG_COMPILER_ASSERT_NDEBUG_EVALUATE=n the default
behavior.

Closes https://github.com/espressif/esp-idf/issues/10136
Closes https://github.com/espressif/esp-idf/issues/2758

Kconfig

@@ -388,6 +388,21 @@ mainmenu "Espressif IoT Development Framework Configuration"
 
         endchoice # assertions
 
+        config COMPILER_ASSERT_NDEBUG_EVALUATE
+            bool "Enable to evaluate the expression inside assert(X) when NDEBUG is set"
+            default y
+            help
+                When NDEBUG is set, assert(X) will not cause code to trigger an assertion.
+                With this option set assert(X) will still evaluate the expression X, though
+                the result will never cause an assertion. This means that if X is a function
+                then the function will be called.
+
+                This is not according to the standard, which states that the assert(X) should
+                be replaced with ((void)0) if NDEBUG is defined.
+
+                In ESP-IDF v6.0 the default behavior will change to "no" to be inline with the
+                standard.
+
         choice COMPILER_FLOAT_LIB_FROM
             prompt "Compiler float lib source"
             default COMPILER_FLOAT_LIB_FROM_RVFPLIB if ESP_ROM_HAS_RVFPLIB

components/newlib/platform_include/assert.h

@@ -30,7 +30,11 @@
 
 #if defined(NDEBUG)
 
+#if CONFIG_COMPILER_ASSERT_NDEBUG_EVALUATE
 #define assert(__e) ((void)(__e))
+#else
+#define assert(__e) ((void)0)
+#endif //CONFIG_COMPILER_ASSERT_NDEBUG_EVALUATE
 
 #elif CONFIG_COMPILER_OPTIMIZATION_ASSERTIONS_SILENT
 

tools/test_apps/system/startup/sdkconfig.ci.no_asserts

@@ -0,0 +1,2 @@
+CONFIG_COMPILER_OPTIMIZATION_ASSERTIONS_DISABLE=y
+CONFIG_COMPILER_ASSERT_NDEBUG_EVALUATE=n